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51.
The Monadic Phases Coding System (MP) and the Maximally Discriminative Facial Movement Coding System (MAX) are both widely used to define and quantify categories of infant affective behavior. To evaluate the validity of extrapolating research findings from one system to another, we used both systems to code videotapes of 12 four-month-old infants engaged in mother–infant interaction. Interobserver agreement was higher with MP; interobserver reliability was equivalent. Point estimates for the percentages of negative and positive, but not interest, expressions were equivalent. MP and MAX generally agreed about the type of expression presented. Intersystem correlations supported the concurrent, but not discriminant, validity of MP and MAX categories. Interest expressions were not orthogonal to negative and positive affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
It has recently been suggested that multiple boosters of tetanus toxoid may enhance serum antitoxin titres but may not necessarily lead to an effective immune response. Tetanus antitoxin titres by haemagglutination inhibition and mouse toxin neutralization tests were determined in sera of 64 children, 5 and 6 years old. Primary vaccination against tetanus was given as four doses of diphtheria-pertussis-tetanus (DPT) vaccine beginning in the second or third month of life, and a booster dose given to schoolchildren at 6 years of age. In our area more than 90% of children receive five doses of tetanus toxoid before their seventh birthday. The children were given 0.5 ml of DPT or DT containing 10 Lf ml-1 tetanus toxoid at each injection. The haemagglutination titres and the toxin neutralization titres were much higher in 6-year-old than in 5-year-old children. We concluded that the fifth dose is an effective booster in 6-year-old children.  相似文献   
53.
A bioassay-guided fractionation of the aerial parts ofSenecio palmensis resulted in the isolation of two sesquiterpenes, 2,10-bisaboladien-1-one and 11-acetoxy-5-angeloyloxy-silphinen-3-one. The bisabolene and the silphinene represented 0.012% and 0.024% of the plant dry weight, respectively. Both compounds showed antifeedant activity againstLeptinotarsa decemlineata larvae and adults in short-term choice and no-choice bioassays. Both compounds were also tested against different species of phytopathogenic fungi. The beetles were more sensitive to these compounds in choice than in no-choice assays, with a gradient of increasing sensitivity from second instars to adults. Bisabolene was 45 times less active as an antifeedant than juglone, which was tested as a positive control. The silphinen was more active than the bisabolene, with a range of activity similar to juglone. Furthermore, exposure of fourth instars to these compounds over a 24-hr period resulted in reduced feeding and growth rates. To distinguish between antifeedant and toxic effects, growth efficiencies were calculated as the slope of the regression of relative growth rate on relative consumption rate. The comparison of these results with those of antifeedant simulation and contact toxicity bioassays indicates that feeding inhibition is the primary mode of action of the bisabolene, while the silphinene shows both antifeedant and toxic effects.  相似文献   
54.
International Journal of Computer-Supported Collaborative Learning - The research landscape displays increasing awareness of the important role of self-regulation and emotions in the process of...  相似文献   
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The present paper focuses on the issue of thermal comfort adaptive criteria and its relevance to the implementation of passive design strategies, in the context of a field work carried out in Portugal. This field work involved monitoring and questionnaires in office buildings existing in Lisbon, as well as other types of buildings, such as homes for the elderly and educational buildings, during summer, winter and mid-season.  相似文献   
57.
Relations between moisture content and water activity of foodstuff can be estimated by determining moisture sorption isotherms. This work aimed at investigating the hygroscopic behavior of dragon fruit powder through sorption isotherms, encapsulated with maltodextrin, and analyzing hygroscopicity, density, and caking degree of samples stored in polyethylene wrappings and laminated coverings at 25°C. Dragon fruit powder showed good results regarding hygroscopicity, density, and caking degree for laminated coverings. In order to describe balance of sorption isotherms, the BET model was the most recommended.  相似文献   
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The effectiveness of grape extracts as food ingredient has been tested in various systems. The objective of this study was to evaluate the efficiency of four concentrations of residues of the wine industry in delaying lipid oxidation in processed chicken meat stored under refrigeration. The development of oxidation during the 14‐day storage was evaluated through the thiobarbituric acid reactive substances method (TBAS). The analyses of phenolic compounds and antioxidant activity were performed in grape residue extracts through DPPH (1,1‐difenil‐2‐picrilidrazil) method, lipid peroxidation inhibition and Rancimat. The profile of polyphenols was determined using reversed‐phase high‐performance liquid chromatography. Isabel grape extract (IGE) and Niagara grape extract (NGE) showed significant content of phenolic compounds. NGE and IGE had high antioxidant activity. The addition of grape extracts significantly increased the oxidative stability of processed and cooked chicken meat during the storage time. The extracts from both grape varieties when applied in concentrations of 40 and 60 mg of GAE, presented results similar to that of Butyl hydroxy toluene (BHT).  相似文献   
60.
In this work, a comparative study about the incorporation of silver nanoparticles (AgNPs) into thin films is presented using two alternative methods, the in situ synthesis process and the layer-by-layer embedding deposition technique. The influence of several parameters such as color of the films, thickness evolution, thermal post-treatment, or distribution of the AgNPs along the coatings has been studied. Thermal post-treatment was used to induce the formation of hydrogel-like AgNPs-loaded thin films. Cross-sectional transmission electron microscopy micrographs, atomic force microscopy images, and UV-vis spectra reveal significant differences in the size and distribution of the AgNPs into the films as well as the maximal absorbance and wavelength position of the localized surface plasmon resonance absorption bands before and after thermal post-treatment. This work contributes for a better understanding of these two approaches for the incorporation of AgNPs into thin films using wet chemistry.  相似文献   
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